The present invention relates to an electrical machine, in particular a claw pole generator.
One of such generators is disclosed for example in the German patent document DE-PS 34 10 760. It however has the disadvantage that because of the groove-shaped intermediate spaces between the claws of the rotor, an insufficient ventilation and thereby also cooling take place. The groove-shaped intermediate spaces between the pole claws form relatively visible passages with the toothed stator wall which runs above. It has been shown that relatively large-volume whirl is produced in these intermediate spaces, and during alternating action with the pole claws or the stator, leads to noise emission. Further, the cross-section of the groove-shaped intermediate spaces periodically changes with the rotary movement due to the structure of the grooveslots in the stator wall. Thereby periodic pressure fluctuations are induced, which lead to noises in corresponding frequency band. The known air guiding vanes inserted in the intermediate spaces of the pole claws can further increase this noise.